What that tough thing is, no one knows.

Republican presidential nominee Donald Trump on Monday said the United States needs to accelerate the fight against the so-called Islamic State, citing the bombings in New York and New Jersey over the weekend as yet another reason the nation ought to be concerned about terrorism.

But when asked by Fox News host Steve Doocy exactly how he would “change the playbook” against the militant group known as ISIS if elected, the New York real estate mogul offered little more than feel-good bromides and chest-pounding machismo like “we have to get tough.”

Doocy: Okay. Change the playbook. How?

Trump: We’re going to have to do something extremely tough over there.

Doocy: Like what?

Trump: Like knock the hell out of them. We have to get everybody together and and we have to lead for a change. Because we’re not knocking them. We’re hitting them every once in a while. We’re hitting them in certain places. We’re being very gentle about it. We have to be very tough and you have other countries who are getting devastated far more than we are and you have to get them together. It’s called leadership. They have to fight. They have to fight the battle. The battle is over there. And we have to fight the battle and we can’t let any more people come into this country and when we have bad ones ― we have people going over fighting for ISIS and coming back and we know they are fighting for ISIS and we take them. Once you leave this country, you fight for ISIS, you never come back.

Trump for over a year claimed he had a secret plan to take out ISIS ― one he said he did not wish to share with America’s enemies in order to stay unpredictable. Earlier this month, he announced he would give the military’s top generals 30 days to submit a plan for soundly defeating ISIS once in the White House. Then, in NBC’s Commander-In-Chief Forum, he claimed that he both did and did not have a plan ― one that could ultimately change once he gets into office.

“When I do come up with a plan that I like and that perhaps agrees with mine, or maybe doesn’t, I may love what the generals come back with,” he said.

To sum up, even though Trump’s plan may or may not fully exist yet ― it is a very, very tough plan that will allow the U.S. to “knock the hell” out of ISIS.

“He keeps saying he has a secret plan. Well, the secret is he has no plan,” the former secretary of state said.

U.S.-led coalition military forces continued to attack ISIS positions on Sunday, conducting 16 strikes in Syria and 12 strikes in Iraq. U.S. and Iraqi forces are also reportedly closing in on Mosul, ISIS’s last major stronghold in Iraq.